Twin Turbo Top Mount Questions?

[paul f]

ok, well im new to the rb scene, ive done all the others though, 1jz,2jz,ka,sr,and even ca, but now i am freshly swapping an rb26dett into my 95 s14 240sx chassis, im am using the car for a DRIFT only setup, but ive fallen in love with the top mount twin turbo setup, the only problem here is i need great response out of this setup. im custom fabricating my own manifolds and downpipes for this setup but i need some in put on the turbo's(remember i need great response), i just pulled out of the car was a sr top mount t3/to4e setup. It made 375(untuned/SAFC)to the wheels but the boost curve was horriable, it was like an on and off switch, i dont want that with this setup, i want boost to build low and smooth curve, im not looking to do much internally unless told its a must, pretty much stock motor execpt headgasket, headstuds, z32 mafs, safc neo, and twin turbo setup im looking for 450hpish realiable but f**king fun and fast with ofcoarse great response, heres the choices that i put infont of myself now but i need other opinions on which set of turbos to run

turbo choice#1- t3/to4e

specs:

60 Trim

compressor-.48 ar

Turbine-.60 ar

turbo# choice2- t3

specs:

50 trim

compressor-.42 ar

turbine- .48

well i could really use all input on which turbos to use in my setup also if you have any other choices i should consider please inform me but no single turbo conversion, or bottom mount turbos, i want top mount twin setup but please feel free to inform!

thank you,

paul f

[zebra]

Why not save your self a few $ and just buy a couple of HKS GT-SS turbos and keep them low mounted.

They will give you the power you want and a nice smooth power curve.

But if you say that you dont want low monted ones you could always top mount them. they are internally gated so plumbing wont be an issue, just heat melting shit due to the high mount.

Also if you wanted more power go HKS GT-RS or 2530s

Or Garrett 2860-5 or 2871s

SO much easier than using dinosaur tech T03s/T04e's

My 2c

[sewid]

Rb26 in a S14 chassis for drift?????

[zebra]

Would sound sweet.

woot 100 posts FTW

[Marco-R34GTT]

May I ask noob question???

Han you have 1 turbo low mount and another high mount???

[zebra]

Dont see why not.....aslong as both manifolds were the same length (or there abouts)

but intake/ exhaust plumbing might get in the way of each other though.

[paul f]

yes, most def. going to place the rb26 in my s14 chassis, thats all i do is drift and this is a drift car only! i like to be diffrent, and ive only seen a few (s13) with rb26's in them for drift, but yes i would def going to keep top mount but whatc ya think out of the two choices above should i run for that nice quick spool and response and still make like 400 450hp!!!??? info please!!

[R31Nismoid]

If your making you own manifolds. Then just high-mount the HKS GT-SS turbos, they are exactly what you want without a doubt.

Although, your better off keeping them low mount for a few reasons, heat and pure cheapness/ease of parts being the main ones

But if you dont mind fabricating everything totally custom then go for it really.

[Adriano]

yes, most def. going to place the rb26 in my s14 chassis, thats all i do is drift and this is a drift car only! i like to be diffrent, and ive only seen a few (s13) with rb26's in them for drift, but yes i would def going to keep top mount but whatc ya think out of the two choices above should i run for that nice quick spool and response and still make like 400 450hp!!!??? info please!!

If your building this as a drift car only, then putting a heavier rb motor up the front of an s-series will give you less than spectacular balance, talk to URAS, he has a lovely rb26s14, and quite often recommends against doing this combo for track work. Not saying it wont be a great car, but would hate to see you do all this work and be beaten by ca's and sr's.

[paul f]

If your building this as a drift car only, then putting a heavier rb motor up the front of an s-series will give you less than spectacular balance, talk to URAS, he has a lovely rb26s14, and quite often recommends against doing this combo for track work. Not saying it wont be a great car, but would hate to see you do all this work and be beaten by ca's and sr's.

i am fully aware of the weight diffrence but i have full and not just coilovers but cage and all suspension setup on my car just for this motor setup! the car will drift perfect with this setup its going rb26 no matter what!

but now here i was thinking, how responsive are the stock twin? because i would like to drive the car with the stock twins so i dont kill my self with out felling the power of the stock motor! i was just gonna throw so new manifolds, dump pipes and full 3inch, no cat, exhaust on it on like 12-15psi! that should get me arond 350-400 right!!! then the mafs/injectors tap out! so that should be a great start?what yeah think?

thank!!

[zebra]

you wont get 400rwhp outta stock twins, you would have to go N1s at least.

Even if your car has suspention/chassis work it wont hide the fact that you will have a great big lump of iron there when the car was made to have a smaller lump of alloy.

Just look at Top Secrets 350Z drifter it has an RB26 (Iron) instead of the VQ35 (alloy) in it and the drivers all say it handles like a lead tipped arrow and wont turn in to corners and wont change direction when sliding.

URAS should be able to tell you more about what there like in a Silvia Chassis

Andrew

[700HP-GTR33]

Paul,

It is good to be different.....and you should do as you like.

Others here say not a RB26...I tend to agree.

Most great drift cars normally use the same motor the manufacturer put in.

they do this and modify/upgrade

1- Suspension.

2- pistons,rods,crank,cams, turbo etc etc.

By putting a stock RB26 motor into a silvia is not going to get you what your looking for.

But if that is not going to faise you.

Get some -7 garrett turbo's(mount them to the top)as R31Nismoid suggested...tomie poncams(drop in)....555 nismo injectors/pump/reg.....pfc....avcr....

Include supporting mods..oil cooler,new oil pump,..etc..etc...

Get a drift tune...1.2 Bar max...then you will smoke those tyres....lol

Good luck with your project.

[sh@un]

240SX?

hello stateside

lol

[R31Nismoid]

Cams, injectors and a reg are not required when using GT-SS turbos IMO.

[Speeddm]

If you want to be a serious drifter DONT go RB in that chassis. You will develop an understering pig of a car. This is the same reason that you dont see big block chevys in grass roots ovaltrack racing. THey just wont turn in unles you have mountans of power and huge balls to mash the gas to create an overster situation when you are heading into a wall at 100k. I raced that way for years. Get it wrong once or twice and you will be praying for a lighter front end. You will push like a Actros.

[mambastu]

If you want to be a serious drifter DONT go RB in that chassis. You will develop an understering pig of a car

Although it has a better front/rear split in standard form than a S14 I have a RS13 with a 25DETT in the front and although I don't drift it I do use it on the odd trackday and its very balanced and in no way understeery when wheeled/tyred adequately and set up properly. Its sister car still has a CA and runs the same suspension and in comparison the RB powered car is actually more planted and turns in better on track.

Heres a little vid from Brands Hatch from a couple of years ago:

http://mambastu.mysite.wanadoo-members.co...._RB25_400TT.mpg

The car was running with a restrictive exhaust to get it quiet enough to run on the day so estimate around 380bhp on the day, I believe that Ferrari 355's are supposed to handle reasonably well...

Edited July 6, 2007 by mambastu

[R31Nismoid]

Are you running a 300rwkw RB25?

Because running a stock-ish powered one is a lot different to running a setup with another 100-140rwkw

[mambastu]

Are you running a 300rwkw RB25?

Because running a stock-ish powered one is a lot different to running a setup with another 100-140rwkw

More like 265 rwkw. It was dynoed at 352rwhp with its road use Blitz NUR on it. On track as I mentioned I have to replace the rear box with a larger and more restrictive 3" box and you can really the difference.

The spec is R33 RB25DET with ported head, twin turbo conversion using standard GTR turbos at 1 bar, 2.5" downpipes, 3" system, no cat. GReddy plenum, 550's, E-manage, R34 GTR intercooler, 3" pipework between turbos and throttlebody.

The point I was trying to make is that by sticking an RB in the front it doesn't turn the car into an understeering pig of a thing like so many people say it will. You can see on the video that the car was able to turn in fine. As Paul f has pointed out, the power delivery is so smooth with a 400/450 hp RB25/26 when compared to a 400/450 hp CA or SR which really helps with getting the power down out of corners. Much more predictable.

Edited July 7, 2007 by mambastu